1. Field of the Invention
The present invention relates to an improved non-caking granular or powdery detergent composition comprising as an active detergent component a surface active agent having a tendency to cake.
2. Description of the Prior Art
Recently, the eutrophication problem caused by the use of sodium tripolyphosphate as a builder in powdery detergents has become important, and it is now desired to reduce the content of sodium tripolyphosphate in detergents. In order to do this, utilization of a surface active agent having a detergency that is not degraded by water hardness has recently been proposed. Alkylethoxy sulfate salts and nonionic surfactants have attracted attention in the art for this purpose. However, powdery detergents containing these surface active agents tend to cake and therefore, it is difficult to put them into practical use.
The present invention relates to improved granular or powdery detergent compositions comprising at least one member selected from hard water-resistant surface active agents such as alkylethoxy sulfate salts, alkylphenylethoxy sulfate salts and ethylene oxide type nonionic surface active agents and from other surface active agents having a tendency to cake, such as branched alkyl sulfate salts, alkanesulfonate salts, vinylidene type olefin-sulfonate salts and internal olefin type sulfonate salts, in which the caking tendency is remarkably reduced.
The caking property of a granular or powdery detergent has a bad effect not only on the manufacturing process but also on the handling of the detergents in households, and the commercial value of a detergent having a tendency to cake is very low. Accordingly, it is very important to prevent caking in granular or powdery detergents.
It is known from experience that the caking property of a granular or powdery detergent is greatly influenced by the kind of the surface active agent employed. For example, sodium benzenesulfonate and sodium toluenesulfonate are effective for preventing caking of detergents containing branched alkylbenzenesulfonate salts and sodium sulfosuccinate is effective for preventing caking of detergents containing linear alkylbenzenesulfonate salts. But it is said that the caking-preventing activity of sodium sulfosuccinate is not high for the former surface active agents and the caking-preventing activity of sodium benzene-sulfonate or sodium toluenesulfonate is not high for the latter surface active agents.
Although the above-mentioned surface active agents having a tendency to cake have an excellent detergent activity, they are disadvantageous in that granular or powdery detergent compositions containing these surface active agents tend to cake and their commercial values are very low.